Investments Short-term and Long-term investments (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Marketable Securities [Line Items]
Short-term Investments	$ 12	$ 14
Equity Method Investments	84	74
Long-term investments	90	435
Restricted Cash Equivalents		$ 96
Restricted Cash Equivalents, Statement of Financial Position [Extensible Enumeration]		Long-term investments
Short-term Investments [Member]
Marketable Securities [Line Items]
Equity Securities, FV-NI, Current	11	$ 11
Debt Securities, Held-to-maturity, Current	0	3
Debt Securities, Time Deposits	1	0
Long-term investments [Member]
Marketable Securities [Line Items]
Equity Method Investments	90	80
Restricted Investments	$ 0	$ 355

Debt Securities, Time Deposits

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current.

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Amount, before allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity), classified as current.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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No definition available.

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Amount of cash equivalents restricted as to withdrawal or usage. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Investments which are not defined as or included in marketable (debt, equity, or other) securities whose use is restricted in whole or in part, generally by contractual agreements or regulatory requirements. For use in an unclassified balance sheet.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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